The present invention relates to an apparatus for use with a spindle of a textile spinning machine and a funnel associated with the spindle. More particularly, the present invention relates to an apparatus for controlling the respective rotational speeds of the spindle and the funnel.
It has been proposed, for example, in German Patent No. A 34 00 327, to provide a separate drive motor to rotate the yarn guide funnel associated with a particular spindle and especially in situations in which the yarn being guided by the funnel to the spindle is relatively fine and not capable of sustaining relatively significant axial tensions without breakage. The funnel is rotated at a speed relative to the rotational speed of the spindle such that the additional rotational force exerted by the yarn traveling from the funnel onto the package being formed on the spindle need only be a relatively small force to bring the rotational speed of the funnel to the rotational speed for winding the yarn onto the spindle. Typically, the rotational speed of the funnel is less than that of the spindle and is less than a predetermined range of rotational speeds, since the rotational speed of the funnel is a function of the varying diameter of the package being formed on the spindle.
In the spinning process, the winding conditions and especially the moment forces on the yarn being wound on the package vary during winding at a constant rate of rotation of the spindle. This is so because the cross sectional diameter of the package being formed on the rotating spindle varies during the winding process. During a period of winding when the cross sectional diameter of the package is relatively large, the funnel must rotate correspondingly faster to constantly deliver the yarn therefrom onto the package as compared to a winding period when the cross sectional diameter of the package is relatively small. During the period of time at which the cross sectional diameter of the package changes from a relatively large value to smaller and smaller values, the danger exists that the funnel, on account of its inertia, will rotate at a rate relative to the rotation of the spindle which is too high, thereby leading to an undesirably low tension in the yarn traveling from the funnel onto the package.
German Patent No. A 34 00 327 also discloses a braking apparatus for applying a constant braking action to the funnel to minimize the influence of the movement of the funnel due to its inertia; this leads to an increased level of complexity and, under certain conditions, to a significant variation in the tension of the yarn.